Nucleic acid hydrogels have been useful for numerous applications including tissue engineering, drug delivery and diagnosis. Previous methods for forming hydrogels can depend on the base pairing of nucleic acids and covalent crosslinking, e.g., ligation with T4 ligase. These processes are complicated for some applications. The invention provides processes for creating nucleic acid based gels without crosslinking to provide flexibility in design and fabrication. Furthermore, the gels provided by the invention have properties that are not achieved through other routes of formation.